Sheet inverter apparatus

ABSTRACT

This invention relates to an improved sheet inverting apparatus for receiving sheets from a processor capable of operating both simplex and duplex modes of operation. The inverting apparatus includes a horizontal vacuum transport which positively positions a sheet onto a vertical vacuum transport upon activation of deflector fingers. The vertical transport reverses in response to signals to deliver the sheet onto the horizontal transport with trailing edge becoming leading edge.

United States Patent Caldwell Nov. 4, 1975 [54] SHEET INVERTER APPARATUS 3,416,791 12/1968 Beckman et a1. 271/65 [75] Inventor: John R. Caldwell Rochester NY 3,419,265 12/1968 Greco et a1. 271/197 X [73] Assignee: erox Corporation, Stamford, Primary Examiner Evon C. Blunk Assistant Examiner-Bruce H. Stoner, Jr. [22] Filed: Apr. 22, 1974 Application Data This invention relates to an improved sheet inverting [63] g g' of 319335 apparatus for receiving sheets from a processor capaa an one ble of operating both simplex and duplex modes of operation. The inverting apparatus includes a horizontal 271/65 198/ vacuum transport which positively positions a sheet E 9 186 197 onto a vertical vacuum transport upon activation of 271/9 225 5 deflector fingers. The vertical transport reverses in re- 28 sponse to signals to deliver the sheet onto the horizon- 5 tal transport with trailing edge becoming leading edge.

[56] References Cited UNITED STATES PATENTS 5 7 Drawmg 3,227,444 1/1966 Egan 271/65 I I20 1Q o 1 119'] Asa I52 Q we o i I Q US. Patent Nov. 4, 1975 Sheet 1 of5 3,917,257

FIG.

US. Patent Nov. 4, 1975 Sheet2of5 3,917,257

U.S. Patent Nov. 4, 1975 Sheet 3 of5 3,917,257

U.S. Patent Nov. 4, 1975 Sheet 4 of5 3,917,257

ISO/5" #52 U.S. Patent Nov. 4, 1975 Sheet 5 of5 3,917,257

SHEET INVERTER APPARATUS This is a continuation of application Ser. No. 319,835, filed Dec. 29, 1972, now abandoned.

This invention relates to sheet inverting apparatus and is especially for use with reproduction systems capable of producing simplex and duplex copies.

With advent of high speed sophisticated copier/duplicator systems there has been a growing concern for the rapid and reliable distribution and handling of the copy sheets in both simplex and duplex sorting modes of operation. In the past sheet inverting devices principally have been used in the handling of documents for recording on both sides as described, for example, in U.S. Pat. Nos. 3,408,140, 3,561,865, and 3,227,444. Also it is known to turn cards, plates, and the like as described, for example, in U.S. Pat. Nos. 2,549,772 and 2,901,246. While the existing devices are suitable for some applications they are not entirely satisfactory for high speed sophisticated reproduction machines capable of operating in simplex and duplex sorting mode of operation.

The present invention is an improved sheet inverting apparatus desirable for use with high speed copier/duplicators of all types including simplex and duplex'systems. Generally speaking, this is accomplished by using vacuum transports which positively position the sheet from a first transport to the second transport and then return it to the first with trailing edge becoming leading edge.

It is therefore a general object of this invention to improve the handling of sheets.

It is another object of this invention to enable inverting copy sheets in a reliable manner.

It is still a further object of the invention to enhance the delivery of copy sheets in both simplex and duplex modes of sorting operation.

It is still a further object of the invention to achieve sheet inversion in a manner which minimizes the effect of sheet characteristics, such as, curl and stiffness.

The above and added advantages of the present invention will be more apparent after reading the following detailed description which refers to accompnaying drawings in which:

FIG. 1 is a perspective view of a high speed copier/- duplicator system including an improved sheet inverter apparatus according to the present invention;

FIG. 2 is a schematic view illustrating the xerographic components of the copier/duplicator system;

FIG. 3 is a side view of the inverter apparatus of the present invention;

FIG. 4 a-c show different views of the inverter apparatus illustrating different sequential operation during sheet inverting; and

FIG. 5 is an isometric view of the inverter apparatus.

FIG. 1 shows a copier/duplicator system generally designated 2 including a copier machine 3, which is a As best shown in FIG. 2, the copier/duplicator system includes an automatic xerographic copying apparatus which includes a photosensitive plate including a photoconductive layer 10 that is placed over a conductive backing. The plate is formed in the shape of a drum 11 and the drum mounted upon a shaft 12 that is journaled for rotation in the machine frame. Basically, the xerographic drum is rotated in the direction indicated so as to pass sequentially through a series of xerographic processing stations. The photosensitive drum and the xerographic processing apparatus are driven at predetermined speed relative to each other from a drive system (not shown) and the operation thereof coordinated in order to produce proper cooperation of the various processing mechanisms.

The original, to be reproduced, is placed upon a transparent horizontally supported platen 4 and the original scanned by means ofa moving optical scanning system and to produce a flowing light image of the original. The scanning system includes an elongated horizontal extended aperture lamp 15 and a movable lens element 18. The lamp and lens element moves in coordination across the object supported upon the platen to focus successive incremental bans of illumination reflected from the object onto the moving drum surface at synchronous speeds therewith. The optical path is folded by means of a pair of image mirrors l9 and 20 interposed between the lens and the drum surface, the drum is first uniformly charged by means of a corona generator 13 positioned in charging station A. Under the influence of the flowing light image, the uniformly charged photoconductive surface is selectively dissipated in the non-image areas to form what is commonly known as a latent electrostatic image.

The latent electrostatic image is carried on the drum surface from the exposure station into the developing station C. The developing station primarily is comprised of a developer housing 22 adapted to support a supply of twocomponent developer material 21 therein. The developer material is transported by means of a bucket system 23 from the bottom of the developer housing to an elevated position where the material is delivered into the active development zone. The developer-material is caused to flow downwardly in contact with the upwardly moving drum surface under closelylcontrolled conditions wherein charged toner particles are attracted from the developer mix into the image areas on the plate surface thus making the image visible.

The moving drum surface next transports the developed xerographic' image to a transfer station D. Cut sheets of final support material are also moved into the transfer station, the backside of the copy sheet is sprayed with an ion discharge from a transfer corotron 23 inducing on the sheet a charge having a polarity and magnitude sufficient to attract the toner material from the drum surface to the final support material. This induced charge also electrostatically tacks the final support material to the drum surface. In order to remove the copy sheet from the drum surface, .a stripper finger 28 is positioned downstream from the transfer corotron. The finger is arranged to move between the drum surface and the copy sheet and lifts the sheet from the drum surface and the copy sheet is directed along a predetermined path of travel into contact with a stationary vacuum transport 29.

Although a preponderance of the toner material is transferred from the drum surface to the copy sheet during the transfer process, invariably some residual toner remains behind on the drum surface after transfer. The residual toner is transported on the drum surface into a cleaning station E where it.is brought under the influence of cleaning corotron 30.adapted toneutralize the electrostatic charge tending to hold the residual toner to the drum surface. The neutralized toner is mechanically cleaned from the drum surface by means of a brush or the like and the toner collected within a housing 31. A conveyor moving inan endless loop through tubes32 transport the collected residual toner back to the developer housing where it is deposited within the developer mix so that it can be once again reused in the xerographic developing process.

The copy sheet, which has been removed from the drum surface after the transfer operation, is moved along stationary transport 29 into fusing station F. The fuser 33 is basically made up of an upper fuser roll 34 and a lower fuser roll 35 mounted in operative relation to each other and arranged to coact so as to support a sheet of material in pressure driving contact therebetween. The lower roll is heated. As the heated roll is rotated in the direction indicated, the heated surface of the lower roll is pressed into intimate contact with the image face of the support sheet. Mechanical and heat energy transported from the roll surface to the support sheet to permanently bond the toner particles to the support material. I

Upon leaving the fuser, the fixed copy sheet is passed through a curvalinear sheet guide system, generally referred to as 39, into cooperating advancing rolls 43 and 44. At this point, depending on the mode of operation selected, the copy sheet is either forwarded directly to the sorter or into the upper supply tray 52 by means of a movable sheet guide 45 before entering the sorter. For simplex copying the copy sheet is advanced directly to the sorterwhich serves to invert the sheet before delivery to one of the trays of a sorter or the like.

It is believed that the foregoing description issufficient for purposes of the present application to show the general operation of a xerographic reproducing machine. For a more detailed explanation of the copier/- duplicator xerographic components referenceis made to US. Pat. No. 3,645,615 entitled Copying Apparatus.

INVERTER APPARATUS (FIGS. 34)

The inverter apparatus 8 includes a horizontal trans port assembly 103 which receives copy sheets from the copier/duplicator and either inverts copy sheets before advancing to the tray assemblies or advance them directly to the tray assemblies according to the modeof operation. Transport assembly 103 includes a series of belts 105 which are formed with holes about one-fourth inch in diameter through which a vacuum is exerted I through a manifold 107 extending along the length of the transport belt 105 as provided by a blower. Belts 105 are mounted ori rolls 109 and 110. Roll 110 ,is driven by a drive motor 111 through belts 113 and 114 and associated pulleys. Positioned above the horizontal transport assembly 103 is a vertical transport assembly having belts117 formed with openings to exert a vacuum force overlying a manifold 119 for transporting the copy sheets as in the case of the horizontal transportassembly. Vacuum is provided by, blower 108. Belts 117 are mounted on rolls 120 and 121. Roll 120 is driven by motor 123 through belts125 and- 127 and. associated pulleys. A

At the entrance to the vertical transport assembly 115 is a deflector assembly 130 which includes a plurality of deflector-members 131 pivotally supported on a. pin member 135. lt will be noted that deflector mem-; bers 131- each have an upwardly curved side portion 137 and a downwardly curved sideportion 139 for a purpose to be described. Deflector members 131 are pivoted on the axis of pin member by moving lever member 140 which is activated by a plunger 143 of a solenoid 145 in response to electrical signals supplied from machine control upon selection of simplex sorting on control panel 5. By this arrangement, copy sheets traveling alongthe horizontal transport 103 are directed upwardly by the upwardly curved surface 137 of the deflector fingers 131 or allowed to pass on to the vertical transport 115, as will become more apparent.

Vertical transport 115 is bi-directional and moves in i a counterclockwise direction except when in the simplex sorting mode of operation. When in the simplex mode of operation as the copy sheet passes a lamp and photocell sensing unit 147 and reflector ,149 the pres ence of the sheet causes asignal to be supplied to ma-.

chine control which reverses the direction of transport Vertical transport 115 continues to move the copy sheets upwardly until such time as the trailing edge of 3 a sheet passes the end of the deflector fingers 131; as can be detected by a lamp and photocell sensing unit with reflector 152 or a signal from machine control after a predetermined time to reverse belts 117. Upon reversal of the belts the copy sheet is guided downwardly over curved surface 139 of the deflector fingers 131 and returned to the horizontal transport assembly 103. It will be now appreciated that the copy sheets being fed onto the horizontal assembly 103 may be inverted at the end of the transport assembly if they are acted upon by the deflector fingers and vertical transport assembly. 115 according to the mode of operation as to whether simplex or duplex copies are desired.

While there have been shown and described and pointed out the fundamental novel features of the inventions as applied to a preferred embodiment, it will be understood that various omissions and substitutions and changes in the form and details of the device illustrated and in its operation may bemade by those skilled in the art without departing from the spirit of the invention. v v

Whatis claimed is: I i

1. In a reproducing system in which simplex and (iiiplex copies are made in a processor and then distributed, an improved. sheet handling apparatus comprisfirsttransport means for receiving copy sheets from a processor, i' second transport means including bi-directionally driven perforated belt means advanced over a vacuum source positioned intermediate to said first transport means and extending in a substantially upward direction,

deflector means positioned at the junction of said first and second transport means including at least one member pivotally mounted to move from a first position away from the sheet path of said first transport means to a second position in a path complementary to each of said transport means,

and control means to move said pivotable member from said first position to said second position to direct the sheet positively upwards onto said second transport means and to reverse the direction of said second transport means to return the sheet positively downwards to said first transport means with trailing edge becoming leading edge.

2. Apparatus according to claim 1 wherein said first transport means includes perforated belt means advanced over a vacuum source.

3. Apparatus according to claim 1 wherein said control includes sensing means positioned in the sheet path.

second transport means including bi-directionally driven perforated belt means advanced over a vacuum source positioned intermediate said first transport means in a substantially upward path,

gate means positioned at the junction of said transport means including at least one movable member formed with a curved surface complementary to the path of said transport means when actuated in response to electrical signals,

logic means supplying signals to actuate said movable member into the sheet path to position the sheet from said first transport means past said gate means and said logic means including sensing means positioned in the sheet path to cause direction of said second transport means to be reversed after movement of the sheet from said first transport means upwards onto said second transport means to return the sheet downwards onto said first transport means with trailing edge becoming leading edge.

5. Apparatus according to claim 4 wherein said first transport means includes perforated belt means advanced over a vacuum source. 

1. In a reproducing system in which simplex and duplex copies are made in a processor and then distributed, an improved sheet handling apparatus comprising: first transport means for receiving copy sheets from a processor, second transport means including bi-directionally driven perforated belt means advanced over a vacuum source positioned intermediate to said first transport means and extending in a substantially upward direction, deflector means positioned at the junction of said first and second transport means including at least one member pivotally mounted to move from a first position away from the sheet path of said first transport means to a second position in a path complementary to each of said transport means, and control means to move said pivotable member from said first position to said second position to direct the sheet positively upwards onto said second transport means and to reverse the direction of said second transport means to return the sheet positively downwards to said first transport means with trailing edge becoming leading edge.
 2. Apparatus according to claim 1 wherein said first transport means includes perforated belt means advanced over a vacuum source.
 3. Apparatus according to claim 1 wherein said control includes sensing means positioned in the sheet path.
 4. Sheet inverting apparatus comprising: first transport means for moving sheets along a predetermined path, second transport means including bi-directionally driven perforated belt means advanced over a vacuum source positioned intermediate said first transport means in a substantially upward path, gate mEans positioned at the junction of said transport means including at least one movable member formed with a curved surface complementary to the path of said transport means when actuated in response to electrical signals, logic means supplying signals to actuate said movable member into the sheet path to position the sheet from said first transport means past said gate means and said logic means including sensing means positioned in the sheet path to cause direction of said second transport means to be reversed after movement of the sheet from said first transport means upwards onto said second transport means to return the sheet downwards onto said first transport means with trailing edge becoming leading edge.
 5. Apparatus according to claim 4 wherein said first transport means includes perforated belt means advanced over a vacuum source. 